This blog addresses the issue of missing items from your inventory.
There are different kinds of problems with missing inventory that can take place; those that are controllable at the viewer or computer end are generally reversible. Problems caused by the Second Life asset server are not always fixable.
It is strongly recommended that you go to a known low lag region to do any of the things listed below.
These are recommended:
*First, check that your inventory has fully loaded. Click on the Recent tab and wait for the inventory counter to stop fetching
Now, reset your inventory filters
click Inventory → Reset Filters in the inventory menu.
Next, if you have another viewer installed, log in on it and see if the items show up there. If they do, then the problem is probably either loading or caching , and you can follow the next set of suggestions. If the items don't show up in any viewer, then there is a good chance they're missing from the asset server, which means the problem may not be fixable.
Now, open your preferences window and click to the network or web tab. It should be the 3rd or 4th tab in the preferences window. Locate the option for clearing disc or inventory cache and enable it. W pop-up will ask if this is your intention. Confirm that it is and click the apply button in the lower corner of your prefs window. Use the ok or close button to close the prefs window.
You are ready to log out! Make sure you choose "last location" as your login destination.
When you log in, it is important to allow your inventory to fully load before doing anything else or going anywhere. esp don't accept any inventory offers at this time.
Drop your draw distance low (for example, to 32 or lower) to minimize the work the viewer is trying to do outside of loading your inventory.
If your inventory seems to be loading slowly, type letters into the search filter. It doesn't matter what letters; the purpose is to prod the search into finding more items. If the fetch stalls again, pick a different letter..
if the inventory is still not fetching all the way, make sure your bandwidth is set optimally in the viewer. Although it may seem counter-intuitive, we have found that lower bandwidth settings usually allow for more reliable inventory loading than higher settings.
Check bandwidth here
Additional notes: If clearing inventory cache does not fix the problem the first time you try it, then it probably won't work on additional attempts, so don't keep doing it (though multiple relogs without cache clears may help). If your inventory is still not loading fully at this point, then the issue is most likely a network or connection problem. General suggestions for problems that may be connection-related are:
If you are on a wireless connection and are able to wire it in, do so.
Reboot your router/modem, leaving it unplugged and unpowered for a minimum of two minutes before powering it back up again.
If you have access to a different connection, try connecting your computer to it temporarily.